Binaural Beats

Binaural beats or binaural tones are auditory processing artifacts, that is, apparent sounds, the perception of which arises in the brain independent of physical stimuli. This effect was discovered in 1839 by Heinrich Wilhelm Dove.

The brain produces a phenomenon resulting in low-frequency pulsations in the loudness of a perceived sound when two tones at slightly different frequencies are presented separately, one to each of a subject's ears, using stereo headphones. A beating tone will be perceived, as if the two tones mixed naturally, out of the brain. The frequency of the tones must be below about 1,000 to 1,500 hertz for the beating to be heard. The difference between the two frequencies must be small (below about 30 Hz) for the effect to occur; otherwise the two tones will be heard separately and no beat will be perceived.

Apparently, these entertain your brain waves to a certain frequency. According to some people, there are various health benefits caused by listening to binaural beats, including increased creativity and relaxation. Companies such as I-Doser sell audio files of binaural beats, claiming that they will reproduce these effects on your brain. They even have some that will supposedly recreate the effects of psychoactive drugs:

This all sounds like a scam to me, however, some people have posted their experiences online. I know that doesn't necessarily mean that these binaural beats produce any real effects on the brain, but I'm no expert on this sort of thing. I'm interested to hear what some of the more informed/educated members of this forum think of this.

They have some free downloads and some in depth information as well. I can't honestly say if it "works" or not, but it's worth a shot. The main point is that you should match whatever frequency your brain is at, so if your brain is closer to an alpha stage and you want to be more awake you need to try to get to the closet frequency of your brain, and slowly shift the frequency up or down that way your brain is more likely to change with it. Throwing some frequency that is no where near your brain wave seems like it would not work at all, and just be an annoying sound.

It's definitely worth a try for concentration and sleep aid, but with all the different variables that would go on with my body i could not testify for it. I think dieting is the most important thing for sleep and for concentration. Also when I concentrate I just need some relaxing sounds usually so I will put on aphex twin's "stone in focus" or something of that sort.

Oh and the main thing is use stereo mode headphones or it completely defeats the purpose.

It's no different from any other music I'd say.
Any song can hit on any number of frequencies that resonate with your brain, this is just ambient music, like any other ambient music.
And no i-doser does not work like advertised. Any experiences are from people dispositioned to create an experience from these things.

It's not the air pressure, it's the electrical signal being sent from your ear drums to your brain, and how your brain perceives this information (as a difference of the two frequencies).

And listening to regular music would not work [in binaural beat theories], Because your brain takes time to "synch up" with the frequency you are going for. Which is why it is important to a try to start off with a frequency closest to your brain's waves.

I could see how people would try to scam selling something like this on the market, but this originally was researched by scientists/psychiatrist and if you look at the link i posted above you can download a frequency simulator for free and try it out.

"Theory Behind BrainWave Generator
EEG and the brain's state
EEG (Electroencephalography) technology is used to measure brain's electrical vibrations from the surface of the scalp. The resulting EEG pattern will contain frequency elements mainly below 30Hz. The frequencies are categorized into four states as follows:
State Frequency range State of mind
Delta 0.5Hz - 4Hz Deep sleep
Theta 4Hz - 8Hz Drowsiness (also first stage of sleep)
Alpha 8Hz - 14Hz Relaxed but alert
Beta 14Hz - 30Hz Highly alert and focused

The dominant frequency in the EEG pattern determines what shall be called the current state of the brain. If the amplitude of the alpha range frequencies is highest, then the brain is said to be in the alpha stage. Note, that other frequencies still exist and it is impossible to give any "exact frequency your brain is operating on". However, later references to the brain states use the simplification of assuming that such a single frequency exists.

Entraining the brain to a desired state
If external stimulus is applied to the brain, it becomes possible to entrain the brain frequency from one stage to another. For example, if a person is in beta stage (highly alert) and a stimulus of 10Hz is applied to his/her brain for some time, the brain frequency is likely to change towards the applied stimulus. The effect will be relaxing to the person. This phenomenon is also called frequency following response.
When the brain's state is close to the applied stimulus, entrainment works more efficiently. Thus, when doing a sweep from one frequency to another, the starting frequency should be as close to your current brain state as possible. The sweep speed should be such that your brain's state changes steadily with it, so that the difference never gets very large. In practice, it is difficult to determine your brain state without extra equipment (like EEG devices). However, you can quite safely assume that during the day your brain is in the beta stage (about 20Hz) and you can start the sweep from there. If you are already somewhat relaxed, you can use a start frequency of 15Hz or a few Hz lower.

Stimulating the brain with binaural beat frequencies
The easiest way of applying stimulus to the brain is via ears. Other senses could be used as well, and vision is actually used quite often (often in addition to hearing). However, humans cannot hear sounds low enough to be useful for brain stimulation, so special techniques must be used. One such special technique used is called binaural beats.
If the left ear is presented with a steady tone of 500Hz and the right ear a steady tone of 510Hz, these two tones combine in the brain. The difference, 10Hz, is perceived by the brain and is a very effective stimulus for brainwave entrainment. This 10Hz is formed entirely by the brain. When using stereo headphones, the left and right sounds do not mix together until in your brain. The frequency difference, when perceived by brain this way, is called a binaural beat.

The effect of the audible frequencies used
To get a stimulus of 10Hz, you may use tones of 500Hz and 510Hz, or 400Hz and 410Hz, or 800Hz and 810Hz, or so on. The only requirements are that the tone is heard well enough and that it is below about 1000Hz. Below 1000Hz, the wavelength of the skull is sufficiently small so that the sound waves curve around it.
You may try out different audible tones with BrainWave Generator and see which ones work best for you.

Altered brain states
As mentioned above, applying a stimulus to the brain will eventually bring the brain's state closer to the stimulus frequency. The following paragraphs describe some possible effects of this.
Note, however, that just passively listening to binaural beats does not necessarily alter your state of consciousness. For example, willingness and ability to relax and focus attention affects how effective the binaural beat stimulus is for inducing state changes.

Helping in meditation
Meditation is essentially about willingly being able to alter one's brain frequency to a desired state. While meditators have traditionally used several years to learn the techniques of meditation, you can now attain the same effect with brainwave entrainment. No special training or great discipline is required. Good meditation frequencies are in the alpha range, from 8Hz to 13Hz.
When a certain brainwave state is experienced and practiced over a period of time, the brain will "learn" the state change and it will become easier to self-produce the desired brainwave state at will. Thus, using brainwave entrainment, you can expect to get some of its effects later even without any entrainment.

Reducing learning time
The theta stage (4hz - 7Hz) has been found to increase learning capabilities. In fact, children spend more time in theta stage than adults, which probably explains the accelerated learning capabilities of children.
Alpha frequencies are also useful for learning purposes. You can play language cassettes, subliminal tapes, etc. during an entrainment session for a maximum effect.

Reducing sleep needs
Some people have found that half an hour a day of the Theta stage can replace up to 4 hours of sleep.
Treatment of certain mental diseases
Brainwave entrainment is used in treatment of depression, low self-esteem, attention deficit disorder, drug and alcohol addiction and autism, to name a few.
Brainwave entrainment has also been found helpful in alleviating headaches and migraines.

Miscellaneous
Some users have also reported increases in their sex drive as a result of brainwave entrainment."

Personally, I've been into meditation and personal development since a kid. I used binaural beats as an early teen and it helped get into an altered state much quicker. I've been using them while learning, working and other internal mental exercises ever since.